RESUMO
Gene expression involving RNA polymerase II is regulated by the concerted interplay between mRNA synthesis and degradation, crosstalk in which mRNA decay machinery and transcription machinery respectively impact transcription and mRNA stability. Rpb4, and likely dimer Rpb4/7, seem the central components of the RNA pol II governing these processes. In this work we unravel the molecular mechanisms participated by Rpb4 that mediate the posttranscriptional events regulating mRNA imprinting and stability. By RIP-Seq, we analysed genome-wide the association of Rpb4 with mRNAs and demonstrated that it targeted a large population of more than 1400 transcripts. A group of these mRNAs was also the target of the RNA binding protein, Puf3. We demonstrated that Rpb4 and Puf3 physically, genetically, and functionally interact and also affect mRNA stability, and likely the imprinting, of a common group of mRNAs. Furthermore, the Rpb4 and Puf3 association with mRNAs depends on one another. We also demonstrated, for the first time, that Puf3 associates with chromatin in an Rpb4-dependent manner. Our data also suggest that Rpb4 could be a key element of the RNA pol II that coordinates mRNA synthesis, imprinting and stability in cooperation with RBPs.
Assuntos
Impressão Genômica , RNA Polimerase II/genética , Processamento Pós-Transcricional do RNA , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Sítios de Ligação , Cromatina/química , Cromatina/metabolismo , Regulação Fúngica da Expressão Gênica , Anotação de Sequência Molecular , Ligação Proteica , RNA Polimerase II/metabolismo , Estabilidade de RNA , RNA Mensageiro/classificação , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Transcrição GênicaRESUMO
The aim of the present study was to determine whether the TRPV1 channel is involved in the onset of sodium appetite. For this purpose, we used TRPV1-knockout mice to investigate sodium depletion-induced drinking at different times (2/24 h) after furosemide administration combined with a low sodium diet (FURO-LSD). In sodium depleted wild type and TRPV1 KO (SD-WT/SD-TPRV1-KO) mice, we also evaluated the participation of other sodium sensors, such as TPRV4, NaX and angiotensin AT1-receptors (by RT-PCR), as well as investigating the pattern of neural activation shown by Fos immunoreactivity, in different nuclei involved in hydromineral regulation. TPRV1 SD-KO mice revealed an increased sodium preference, ingesting a higher hypertonic cocktail in comparison with SD-WT mice. Our results also showed in SD-WT animals that SFO-Trpv4 expression increased 2 h after FURO-LSD, compared to other groups, thus supporting a role of SFO-Trpv4 channels during the hyponatremic state. However, the SD-TPRV1-KO animals did not show this early increase, and maybe as a consequence drank more hypertonic cocktail. Regarding the SFO-NaX channel expression, in both genotypes our findings revealed a reduction 24 h after FURO-LSD. In addition, there was an increase in the OVLT-NaX expression of SD-WT 24 h after FURO-LSD, suggesting the participation of OVLT-NaX channels in the appearance of sodium appetite, possibly as an anticipatory response in order to limit sodium intake and to induce thirst. Our work demonstrates changes in the expression of different osmosodium-sensitive channels at specific nuclei, related to the body sodium status in order to stimulate an adequate drinking.
Assuntos
Apetite/genética , Encéfalo/metabolismo , Dieta Hipossódica , Sódio na Dieta/administração & dosagem , Canais de Cátion TRPV/fisiologia , Animais , Apetite/efeitos dos fármacos , Dieta Hipossódica/efeitos adversos , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Líquidos/genética , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Alimentos/genética , Furosemida/farmacologia , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Sódio na Dieta/metabolismo , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo , Sede/efeitos dos fármacos , Sede/fisiologiaRESUMO
Epigenetic consequences of exposure to psychostimulants are substantial but the relationship of these changes to compulsive drug taking and abstinence is not clear. Here, we used a paradigm that helped to segregate rats that reduce or stop their methamphetamine (METH) intake (nonaddicted) from those that continue to take the drug compulsively (addicted) in the presence of footshocks. We used that model to investigate potential alterations in global DNA hydroxymethylation in the nucleus accumbens (NAc) because neuroplastic changes in the NAc may participate in the development and maintenance of drug-taking behaviors. We found that METH-addicted rats did indeed show differential DNA hydroxymethylation in comparison with both control and nonaddicted rats. Nonaddicted rats also showed differences from control rats. Differential DNA hydroxymethylation observed in addicted rats occurred mostly at intergenic sites located on long and short interspersed elements. Interestingly, differentially hydroxymethylated regions in genes encoding voltage (Kv1.1, Kv1.2, Kvb1 and Kv2.2)- and calcium (Kcnma1, Kcnn1 and Kcnn2)-gated potassium channels observed in the NAc of nonaddicted rats were accompanied by increased mRNA levels of these potassium channels when compared with mRNA expression in METH-addicted rats. These observations indicate that changes in differentially hydroxymethylated regions and increased expression of specific potassium channels in the NAc may promote abstinence from drug-taking behaviors. Thus, activation of specific subclasses of voltage- and/or calcium-gated potassium channels may provide an important approach to the beneficial treatment for METH addiction.
Assuntos
Metilação de DNA/efeitos dos fármacos , Metanfetamina/metabolismo , Canais de Potássio/efeitos dos fármacos , Animais , Comportamento Aditivo , Estimulantes do Sistema Nervoso Central , DNA/metabolismo , Metilação de DNA/genética , Masculino , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/metabolismo , Potássio/metabolismo , Canais de Potássio/genética , Canais de Potássio/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
The RPB1 mutants in the foot region of RNA polymerase II affect the assembly of the complex by altering the correct association of both the Rpb6 and the Rpb4/7 dimer. Assembly defects alter both transcriptional activity as well as the amount of enzyme associated with genes. Here, we show that the global transcriptional analysis of foot mutants reveals the activation of an environmental stress response (ESR), which occurs at a permissive temperature under optimal growth conditions. Our data indicate that the ESR that occurs in foot mutants depends mostly on a global post-transcriptional regulation mechanism which, in turn, depends on Rpb4-mRNA imprinting. Under optimal growth conditions, we propose that Rpb4 serves as a key to globally modulate mRNA stability as well as to coordinate transcription and decay. Overall, our results imply that post-transcriptional regulation plays a major role in controlling the ESR at both the transcription and mRNA decay levels.
Assuntos
RNA Polimerase II/genética , Proteínas de Saccharomyces cerevisiae/genética , Estresse Fisiológico/genética , Transcrição Gênica , Impressão Molecular , Mutação , Estabilidade de RNA/genética , RNA Mensageiro/genética , Saccharomyces cerevisiaeRESUMO
AIMS: To evaluate the presence of perforating cutaneous vessels (PCV) in different lower limb acupuncture points (AP) using thermography. MATERIAL AND METHODS: An analytical cross-sectional study was performed on the two lower limbs (n=6) of volunteer subjects. In total, 144 AP and 144 control points (CP) were analysed, one for each AP. First, the AP and CP were located on each individual. Subsequently, both the real and thermographic images were created. In the real images, the location of the AP and the established CP were highlighted with boxes. FLIR Tools Plus and Physio Thermal Imaging software were used to merge the real image with the AP and the CP and to merge the thermographic image with the PCV. By superimposing both images, we were able to verify the presence of PCV among the AP and CP. RESULTS: PCV were identified in 87.5% of the 144 AP examined and in 18.1% of the respective CP. All the AP had a higher percentage of PCV compared to their respective CP, with statistically significant differences in all points, except for ST33 and ST34. The probability of finding PCV in AP was 11 times higher than the probability of not finding it. DISCUSSION: Thermography may serve as a useful tool in the assessment and treatment of patients using acupuncture. The presence of PCV in the area of the acupuncture needle insertion could partially influence the effects generated by the acupuncture technique from the vascular autonomic point of view. CONCLUSIONS: There is a high proportion of PCV in the AP area located in the lower limb.
RESUMO
Antibiotics have been beneficial for human and animal health. However, an excessive use in livestock and a deficient management of the carcasses can lead to adverse effects in the scavengers that ingest them, especially in "supplementary feeding sites" (SFS). The aim of this study was to assess the potential risk of exposure to antibiotics for an endangered population of Cinereous vultures (Aegypius monachus) from southeastern Portugal. Hence, a multi-residue method based on QuEChERs was adapted and validated to analyse, in small volumes of tissues, the most frequent antibiotics used in livestock. The method was applied to 87 samples of liver, muscle and kidney from 7 goats and 25 sheep disposed in SFS. According to questionnaires to farmers, the animals had not been treated with antibiotics, but analyses showed residues in 29% of the samples. Antibiotics were more frequent in goats (42.9%) than in sheep (24.2%), and oxytetracycline and trimethoprim were the most common (both 13.8%). Oxytetracycline, the most common antibiotic for livestock in Portugal, showed the highest concentration (1452.68â¯ngâ¯g-1). To our knowledge, this is the first study of presence of antibiotics in carrion from SFS. The concentrations of antibiotics in carrion do not seem to pose a risk of acute intoxication for adult Cinereous vultures. However, subtle and likely chronic exposure with unknown health consequences may occur, which requires more research. Moreover, the results of this first study can be used in future studies to assess the risk for avian scavengers.
Assuntos
Antibacterianos/análise , Monitoramento Ambiental , Poluentes Ambientais/análise , Falconiformes/fisiologia , Animais , Aves , Gado , PortugalRESUMO
The aim of this study was to evaluate technological and antioxidant properties, including in vitro bioaccessibility of polyphenols, conferred on raw anchovy mince by the addition of polyphenol-rich grape pomace dietary fibre at different concentrations. For this purpose, headed and gutted anchovy was heat-flayed, deboned and mixed with 0%, 2%, 3%, 4% grape pomace dietary fibre. A significant increase (P<0.05) in the concentration of polyphenols and associated antioxidant capacity was detected when grape pomace dietary fibre was incorporated in a proportion of at least 2% of the final mixture. In vitro digestion showed that the higher the grape pomace dietary fibre content, the higher was the proportion of polyphenols reaching the large intestine. Additionally, it was observed that the ABTS (2,2'-azino-bis(3-ethylbenzo-thiazoline-6-sulfonic acid) assay seems to be more suitable for evaluating antioxidant capacity in this kind of samples than FRAP (Ferric Reducing Antioxidant Power) assay. Technological properties such as mechanical and water holding, as well as sensory scores, indicated excellent qualities and acceptability of all samples. Hence, given the good acceptance of these samples, it should be feasible to make fish products based on mince anchovy as a means of increasing dietary intake of polyphenols with antioxidant capacity, especially considering the high concentration of polyphenols bioaccessible in the large intestine.
Assuntos
Fibras na Dieta/análise , Produtos Pesqueiros/análise , Peixes , Polifenóis/química , Polifenóis/farmacocinética , Vitis/química , Animais , Antioxidantes/análise , Disponibilidade Biológica , Fenômenos Químicos , Comportamento do Consumidor , Manipulação de Alimentos/métodos , Alimentos Fortificados/análise , Frutas/química , Humanos , Intestino Grosso/metabolismo , Polifenóis/análise , Sensação , Resistência ao CisalhamentoAssuntos
RNA Polimerase II , Proteínas de Saccharomyces cerevisiae , RNA Polimerase II/metabolismo , RNA Mensageiro/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Transcrição GênicaRESUMO
In order to establish the involvement of particular neurochemical brain groups in the response to blood volume expansion, we analyzed Fos-labeling in combination with immunolabeling for serotonin, tyrosine hydroxylase, vasopressin and oxytocin, 90 min after a sham or i.v. isotonic blood volume expansion (BVE) in unanesthetized, unrestrained rats. We also examined the changes in concentration of oxytocin, atrial natriuretic peptide and vasopressin plasma, induced by blood volume load, to confirm our previous studies. The results demonstrate the participation of specific paraventricular and supraoptic nucleus groups of cells (oxytocinergic-vasopressinergic), serotoninergic dorsal raphe nucleus cells and catecholaminergic A1/A2/A6 groups (in the caudal ventrolateral medulla, nucleus of the solitary tract and locus coeruleus respectively), in the regulatory response to BVE. They provide detailed neuroanatomical evidence to support previous observations showing the contribution of these neurochemical systems in the neural, behavioral and endocrine response to isotonic BVE.
Assuntos
Química Encefálica , Encéfalo/fisiologia , Volume Plasmático/fisiologia , Animais , Fator Natriurético Atrial/sangue , Pressão Sanguínea/fisiologia , Encéfalo/citologia , Contagem de Células/métodos , Frequência Cardíaca/fisiologia , Masculino , Neurônios/metabolismo , Ocitocina/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Wistar , Serotonina/metabolismo , Fatores de Tempo , Tirosina 3-Mono-Oxigenase/metabolismo , Vasopressinas/metabolismoRESUMO
The aim of the present work is to analyze how prenatal binge-like ethanol exposure to a moderate dose (2.0 g/kg; group Pre-EtOH) during gestational days (GD) 17-20 affects hydroelectrolyte regulatory responses. This type of exposure has been observed to increase ethanol consumption during adolescence (postnatal day 30-32). In this study we analyzed basal brain neural activity and basal-induced sodium appetite (SA) and renal response stimulated by sodium depletion (SD) as well as voluntary ethanol consumption as a function of vehicle or ethanol during late pregnancy. In adolescent offspring, SD was induced by furosemide and a low-sodium diet treatment (FURO+LSD). Other animals were analyzed in terms of immunohistochemical detection of Fra-like (Fra-LI-ir) protein and serotonin (5HT) and/or vasopressin (AVP). The Pre-EtOH group exhibited heightened voluntary ethanol intake and a reduction in sodium and water intake induced by SD relative to controls. Basal Na and K concentrations in urine were also reduced in Pre-EtOH animals while the induced renal response after FURO treatment was similar across prenatal treatments. However, the correlation between urine volume and water intake induced by FURO significantly varied across these treatments. At the brain level of analysis, the number of basal Fra-LI-ir was significantly increased in AVP magnocellular neurons of the paraventricular nucleus (PVN) and in 5HT neurons in the dorsal raphe nucleus (DRN) in Pre-EtOH pups. In the experimental group, we also observed a significant increase in Fra-LI along the nucleus of the solitary tract (NTS) and in the central extended amygdala nuclei. In summary, moderate Pre-EtOH exposure produces long-lasting changes in brain organization, affecting basal activity of central extended amygdala nuclei, AVP neurons and the inhibitory areas of SA such as the NTS and the 5HT-DRN. These changes possibly modulate the above described variations in basal-induced drinking behaviors and renal regulatory responses.
Assuntos
Consumo Excessivo de Bebidas Alcoólicas , Encéfalo/metabolismo , Efeitos Tardios da Exposição Pré-Natal , Equilíbrio Hidroeletrolítico/fisiologia , Animais , Encéfalo/patologia , Modelos Animais de Doenças , Comportamento de Ingestão de Líquido/fisiologia , Eletrólitos/urina , Feminino , Imuno-Histoquímica , Masculino , Neurônios/metabolismo , Neurônios/patologia , Gravidez , Distribuição Aleatória , Ratos Wistar , Sódio na DietaRESUMO
Exposure to an altered osmotic environment during a pre/postnatal period can differentially program the fluid intake and excretion pattern profile in a way that persists until adulthood. However, knowledge about the programming effects on the underlying brain neurochemical circuits of thirst and hydroelectrolyte balance, and its relation with behavioral outputs, is limited. We evaluated whether early voluntary intake of hypertonic NaCl solution may program adult offspring fluid balance, plasma vasopressin, neural activity, and brain vasopressin and angiotensinergic receptor type 1a (AT1a)-receptor gene expression. The manipulation (M) period covered dams from 1 week before conception until offspring turned 1-month-old. The experimental groups were (i) Free access to hypertonic NaCl solution (0.45 M NaCl), food (0.18% NaCl) and water [M-Na]; and (ii) Free access to food and water only [M-Ctrol]. Male offspring (2-month-old) were subjected to iv infusion (0.15 ml/min) of hypertonic (1.5M NaCl), isotonic (0.15M NaCl) or sham infusion during 20 min. Cumulative water intake (140 min) and drinking latency to the first lick were recorded from the start of the infusion. Our results indicate that, after systemic sodium overload, the M-Na group had increased water intake, and diminished neuronal activity (Fos-immunoreactivity) in the subfornical organ (SFO) and nucleus of the solitary tract. They also showed reduced relative vasopressin (AVP)-mRNA and AT1a-mRNA expression at the supraoptic nucleus and SFO, respectively. The data indicate that the availability of a rich source of sodium during the pre/postnatal period induces a long-term effect on drinking, neural activity, and brain gene expression implicated in the control of hydroelectrolyte balance.
Assuntos
Encéfalo/citologia , Ingestão de Líquidos/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Neurônios/metabolismo , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Solução Salina Hipertônica/efeitos adversos , Fatores Etários , Animais , Animais Recém-Nascidos , Feminino , Seguimentos , Masculino , Gravidez , Ratos , Ratos Wistar , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 1 de Angiotensina/metabolismo , Fatores de Tempo , Vasopressinas/genética , Vasopressinas/metabolismo , Equilíbrio Hidroeletrolítico/efeitos dos fármacosRESUMO
Our aim was to analyze the participation of inhibitory and stimulatory signals in the temporal dissociation between sodium depletion (SD) induced by peritoneal dialysis (PD) and the appearance of sodium appetite (SA), particularly 2h after PD, when the rats are hypovolemic/natremic but SA is not evident. We investigated the effects of bilateral injections of the serotonin (5-HT) receptor antagonist, methysergide, into the lateral parabrachial nucleus (LPBN) on hypertonic NaCl and water intake 2h vs. 24h after PD. We also studied plasma renin activity (PRA) and aldosterone (ALDO) concentration 2h vs. 24h after PD. Additionally, we combined the analysis of brain Fos immunoreactivity (Fos-ir) with the detection of double immunoreactivity in 5HT and oxytocinergic (OT) cells 2h after PD. Bilateral LPBN injections of methysergide (4µg/200nl at each site) increased NaCl intake when tested 2h after PD compared to controls. We found a significant increase in PRA and ALDO concentration after PD but no differences between 2 and 24h after PD. We also found for the first time a significant increase 2h after PD in the number of Fos-ir neurons in the brainstem nuclei that have been shown to be involved in the inhibition of SA. In summary, the results show that 5HT-mechanisms in the LPBN modulate sodium intake during the delay of SA when the renin angiotensin aldosterone system (RAAS) is increased. In addition, the activation of brainstem areas previously associated with the satiety phase of SA is in part responsible for the temporal dissociation between SD and behavioral arousal.
Assuntos
Apetite/fisiologia , Encéfalo/metabolismo , Comportamento de Ingestão de Líquido/fisiologia , Sódio/metabolismo , Administração Oral , Aldosterona/sangue , Animais , Apetite/efeitos dos fármacos , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Glucose/administração & dosagem , Masculino , Metisergida/farmacologia , Proteínas Oncogênicas v-fos/metabolismo , Ocitocina/metabolismo , Núcleos Parabraquiais/efeitos dos fármacos , Ratos , Ratos Wistar , Renina/sangue , Solução Salina Hipertônica/administração & dosagem , Serotonina/metabolismo , Antagonistas da Serotonina/farmacologia , Fatores de Tempo , Equilíbrio HidroeletrolíticoRESUMO
Recent papers have provided insight into the cytoplasmic assembly of RNA polymerase II (RNA pol II) and its transport to the nucleus. However, little is known about the mechanisms governing its nuclear assembly, stability, degradation, and recycling. We demonstrate that the foot of RNA pol II is crucial for the assembly and stability of the complex, by ensuring the correct association of Rpb1 with Rpb6 and of the dimer Rpb4-Rpb7 (Rpb4/7). Mutations at the foot affect the assembly and stability of the enzyme, a defect that is offset by RPB6 overexpression, in coordination with Rpb1 degradation by an Asr1-independent mechanism. Correct assembly is a prerequisite for the proper maintenance of several transcription steps. In fact, assembly defects alter transcriptional activity and the amount of enzyme associated with the genes, affect C-terminal domain (CTD) phosphorylation, interfere with the mRNA-capping machinery, and possibly increase the amount of stalled RNA pol II. In addition, our data show that TATA-binding protein (TBP) occupancy does not correlate with RNA pol II occupancy or transcriptional activity, suggesting a functional relationship between assembly, Mediator, and preinitiation complex (PIC) stability. Finally, our data help clarify the mechanisms governing the assembly and stability of RNA pol II.
Assuntos
RNA Polimerase II/química , RNA Polimerase II/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , RNA Polimerases Dirigidas por DNA/química , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/metabolismo , Estabilidade Enzimática/genética , Genes Fúngicos , Complexo Mediador/metabolismo , Modelos Biológicos , Mutação , Estrutura Terciária de Proteína , Subunidades Proteicas , Capuzes de RNA/metabolismo , RNA Polimerase II/genética , RNA Fúngico/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteína de Ligação a TATA-Box/metabolismo , Transcrição GênicaRESUMO
Mycophenolic acid (MPA) is an immunosuppression agent for the prophylaxis of organ rejection in patients receiving allogeneic transplants. The drug is administered based in 2 formulations, mycophenolate mofetil (MMF) and enteric-coated mycophenolate sodium (EC-MPS). MPA acts by specific, reversible, uncompetitive inhibition of inosine monophosphate dehydrogenase (IMPDH) and thus blocks the proliferation of both T- and B-activated lymphocytes. Therapeutic drug monitoring (TDM) constitutes an important part of immunosuppressive treatment because of the demonstrated significant intraindividual and interindividual variability of its pharmacokinetic behavior. TDM is required to optimize immunosuppressive efficacy. We present the analytical validation of a homogeneous particle-enhanced turbidimetric inhibition immunoassay (PETINIA) technique for determination of MPA in human plasma, and compare with a homogeneous enzyme immunoassay technique (EMIT; reference method), both methods adapted on a Dimension analyzer (Siemens). We examined 50 human plasma samples from kidney transplant recipients treated with MMF or EC-MPA, which were analyzed simultaneously by both methods. The interassay precision was 5.95% at a concentration of 1.0 µg/mL, 3.47% at 7.5 µg/mL, and 3.75% at 12.0 µg/mL. The bias of PETINIA-MPA for each of the 3 quality control sample was <3.0%. Least squares linear regression yielded an r-value of 0.994 with the following linear regression equation: PETINIA = 0.939 * EMIT - 0.063. Bland-Altman comparison presented a mean negative difference of -0.312 µg/mL (standard deviation [SD], 0.441), namely, -7.6% for PETINIA-MPA. The PETINIA assay for monitoring MPA concentrations is an acceptable method for routine clinical use, with interassay imprecision (% coefficient of variation) ranging from 5.9% to 3.7% below and above the therapeutic concentration range, respectively. In conclusion, MPA-EMIT and PETINIA-MPA methods on Dimension analyzer have a good correlation (r = 0.994), but PETINIA-MPA method demonstrates a negative average difference of -7.6% in comparison with EMIT-MPA method.
Assuntos
Monitoramento de Medicamentos/métodos , Imunoensaio , Imunossupressores/sangue , Transplante de Rim/imunologia , Ácido Micofenólico/análogos & derivados , Química Farmacêutica , Monitoramento de Medicamentos/normas , Humanos , Imunoensaio/normas , Técnicas Imunoenzimáticas , Imunossupressores/química , Análise dos Mínimos Quadrados , Modelos Lineares , Ácido Micofenólico/sangue , Ácido Micofenólico/química , Nefelometria e Turbidimetria , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Comprimidos com Revestimento EntéricoRESUMO
Osmoregulatory mechanisms can be vulnerable to electrolyte and/or endocrine environmental changes during the perinatal period, differentially programming the developing offspring and affecting them even in adulthood. The aim of this study was to evaluate whether availability of hypertonic sodium solution during the perinatal period may induce a differential programming in adult offspring osmoregulatory mechanisms. With this aim, we studied water and sodium intake after Furosemide-sodium depletion in adult offspring exposed to hypertonic sodium solution from 1 week before mating until postnatal day 28 of the offspring, used as a perinatal manipulation model [PM-Na group]. In these animals, we also identified the cell population groups in brain nuclei activated by Furosemide-sodium depletion treatment, analyzing the spatial patterns of Fos and Fos-vasopressin immunoreactivity. In sodium depleted rats, sodium and water intake were significantly lower in the PM-Na group vs. animals without access to hypertonic sodium solution [PM-Ctrol group]. Interestingly, when comparing the volumes consumed of both solutions in each PM group, our data show the expected significant differences between both solutions ingested in the PM-Ctrol group, which makes an isotonic cocktail; however, in the PM-Na group there were no significant differences in the volumes of both solutions consumed after Furosemide-sodium depletion, and therefore the sodium concentration of total fluid ingested by this group was significantly higher than that in the PM-Ctrol group. With regard to brain Fos immunoreactivity, we observed that Furosemide-sodium depletion in the PM-Na group induced a higher number of activated cells in the subfornical organ, ventral subdivision of the paraventricular nucleus and vasopressinergic neurons of the supraoptic nucleus than in the PM-Ctrol animals. Moreover, along the brainstem, we found a decreased number of sodium depletion-activated cells within the nucleus of the solitary tract of the PM-Na group. Our data indicate that early sodium availability induces a long-term effect on fluid drinking and on the cell activity of brain nuclei involved in the control of hydromineral balance. These results also suggest that availability of a rich source of sodium during the perinatal period may provoke a larger anticipatory response in the offspring, activating the vasopressinergic system and reducing thirst after water and sodium depletion, as a result of central osmosensitive mechanism alterations.
Assuntos
Solução Salina Hipertônica/farmacologia , Equilíbrio Hidroeletrolítico/efeitos dos fármacos , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Líquidos/fisiologia , Feminino , Furosemida/farmacologia , Masculino , Imagem Molecular/métodos , Imagem Molecular/estatística & dados numéricos , Gravidez , Ratos , Ratos Wistar , Sódio/deficiência , Sódio/metabolismo , Equilíbrio Hidroeletrolítico/fisiologiaRESUMO
In the present study, we investigated the degree to which ß-endorphin plays a role in the alpha 2-adrenergic/imidazoline receptor agonist attenuation of salt appetite. In order to evaluate whether the inhibitory action of clonidine (an α2-adrenergic/imidazoline receptor agonist) on induced sodium intake is mediated by the ß-endorphinergic system, we used a ß-endorphin deficient mouse line. ß-endorphin knockout (ßend(-/-)), heterozygous (ßend(+/-)) and wild-type (ßend(+/+)) mice were submitted to acute sodium depletion by a combined treatment of furosemide and low sodium diet and, 20h later, were administered with clonidine (0.5mg/kg). An hour later, the animals were subjected to a two-bottle choice test (water/2% NaCl). The results indicate that clonidine administration during the first stage of the test exerts an equivalent inhibition on sodium intake regardless of the genotype; however, in the final stage of the test, a reversal of the inhibitory response on induced sodium appetite becomes evident in the mice lacking ß-endorphin. Moreover no differences in dipsogenic response were observed between the genotypes. Considering these results and the fact that plasma half-life of clonidine at the dose administered is approximately 3h, it is possible to speculate that the inhibitory effect of clonidine on sodium appetite may be independent of ß-endorphin modulation during the first stage; however, the long-lasting inhibitory effect of clonidine may be mediated by the ß-endorphinergic system. This evidence supports the existence of adrenergic and ß-endorphinergic system interaction in the osmoregulatory response to achieve sodium balance.
Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Apetite/efeitos dos fármacos , Clonidina/farmacologia , Receptores de Imidazolinas/agonistas , Cloreto de Sódio na Dieta/farmacologia , beta-Endorfina/fisiologia , Animais , Clonidina/administração & dosagem , Ingestão de Líquidos/fisiologia , Furosemida/farmacologia , Camundongos , Camundongos Endogâmicos , Receptores Adrenérgicos alfa 2/metabolismoRESUMO
BACKGROUND: Sirolimus (SRL) is a macrocyclic lactone, indicated for prevention of organ rejection after kidney transplantation. Therapeutic drug monitoring of this agent constitutes an important part to immunosuppressive treatment because of its narrow window of therapeutic efficacy. Routine methods include manual pretreatment of samples. The aim of this study was to evaluate the performance characteristics of an automated immunoassay that does not require manual pretreatment to quantify SRL in whole blood on the Dimension analyzer. METHODS: We examined 50 whole blood samples collected routinely from kidney transplant patients treated with SRL. The samples were analyzed simultaneously by an immunoassay on an IMx analyzer (reference method), which requires manual pretreatment step versus a totally automated immunoassay on the Dimension analyzer, which does not require this pretreatment. RESULTS: The Dimension SRL assay had a functional sensitivity of ≤2.4 ng/mL. Total imprecision was 15.6% at a concentration of 2.8 ng/mL; 10% at 7.9 ng/mL; and 5.2% at 18.4 ng/mL. Least-squares linear regression analysis yielded an r-value of 0.973 with the following equation: SRL-D=1.204*SRL-IMx-0.251. Bland-Altman comparison showed a mean positive difference of 1.38 ng/mL (95% confidence interval, -1.10 to 3.82), namely, 17.2% for SRL Dimension. The Dimension assay to monitor SRL concentrations was an acceptable method for routine clinical use, with total assay imprecision (%CV) ranging from 10.0% to 5.2% within and above the therapeutic concentration range, respectively. CONCLUSION: SRL IMx and Sirolimus Dimension methods show a good correlation (r=0.973), but the SRL Dimension method demonstrated a positive average difference of 17.2% compared with the IMx method. The Dimension assay to monitor whole blood SRL concentration does not require a manual pretreatment step, reducing turnaround time and making this method an attractive alternative for SRL analysis.
Assuntos
Automação , Imunoensaio/métodos , Imunossupressores/sangue , Sirolimo/sangue , Humanos , Limite de Detecção , Reprodutibilidade dos TestesRESUMO
The blood lead of 23 griffon vultures (Gyps fulvus) trapped in 2003 was analyzed in order to evaluate exposure to lead in the vulture population of Cazorla Natural Park (in southern Spain). In 2001 the use of leaded gasoline in vehicles was banned in the European Union; however, lead ammunition is still used in Spain in big-game hunting for red deer, fallow deer, mouflon, and wild boar, which are ingested by vultures from September to March. The mean concentration of lead in blood was 43.07 +/- 31.96 microg/dL with a range of 17.39-144.80 microg/dL. Only two vultures had lead levels below 20 microg/dL, and two others had blood lead concentrations close to 150 microg/dL. In view of the results, we think the population of vultures from Cazorla Natural Park is suffering subclinical exposure to lead, with some individuals exposed to high toxicity risk. We concluded that ingestion of lead in the metallic form alone is sufficient to produce these blood lead concentrations, and we recommend the prohibition of lead ammunition for big-game hunting in order to preserve the vulture population.
Assuntos
Poluentes Ambientais/sangue , Falconiformes/sangue , Chumbo/sangue , Animais , EspanhaRESUMO
Problems related to psychometric measures of intelligence are discussed with regard to both the general characteristics and metric properties (validity, reliability and sensibility) of mental tests, and interindividual differences (cultural background, education, life contents and age-cohorts). Currently used standard intelligence tests explore the structure of intelligence only in part, so a distinction must be made between true actual intelligence, potential inheritance of intelligence, and psychometrical or scored intelligence. The correct use of intelligence testing, however, does provide some relevant and objective information regarding the evolution of cognitive structure during adulthood and in relationship to aging. Cognitive performance in the elderly follows a downward curve that is not explained as a result of aging on physiological responses (i.e., reaction time delay, signal-noise ratio in the CNS, degenerative loss of cortical cells, etc.). Biologically based theories of intelligence cannot explain the large individual differences in cognitive abilities observed in subjects who have very similar physical characteristics. Cognitive approaches to intelligence enable us to better understand the causal factors of the cognitive deficits in the elderly, and an interactive model permits us to fully integrate both the individual differences in cognitive abilities and the large consistency in performances. We compared the cognitive performances of two groups of elderly subjects, ranging in age from 65 to 97 years; we observed some statistically significant effects on cognitive deficit that could be explained as fully deriving from emotional and extra-cognitive responses to environmental changes.
Assuntos
Envelhecimento/psicologia , Transtornos Cognitivos/etiologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Transtornos Cognitivos/psicologia , Meio Ambiente , Feminino , Humanos , Inteligência , Testes de Inteligência , Masculino , Modelos PsicológicosRESUMO
Psychological relationship dentist-patient and psychological education of the dentist are in special dental care very important. In fact the patients with medically complex conditions--patients at risk--often present an altered perception of the reality and behavior, therefore they seldom can co-operate during the operating session. It is then very important to carry-out a psycho-pathological diagnosis, which can avoid a dentist's wrong behavior. Anxiety rate, pathological personality and comprehension level are finally studied.